Patent GB-1467411-A (GB)
Title: Elevator system
IPC: B66B5/02
Filed: 1974-02-27
Abstract: 1467411 Multi-car systems WESTINGHOUSE ELECTRIC CORP 27 Feb 1974 [12 March 1973] 8812/74 Heading G3N In a multi-car lift control system, in which each of the cars, A, B, C, are controlled via an associated car selector, all corridor calls are transmitted to the selectors of all the cars, each selector having inhibit inputs such that, under control of a system processor, which may be hard wired or programmable, the inhibits are operated so that the cars respond to corridor calls according to one or other of the following schemes. (i) Each corridor call is allocated to one or other of the cars (ii) Upon allocation of a corridor call from a reference floor to one of the cars, such car responds to all calls, in either direction sense, from the reference landing, such direction being independent of car motion direction to the reference landing, or direction of motion to the most remote of the enabled group of corridor calls if such is further from the car than the reference landing. (iii) A read-only memory of the system processor is set so that each car responds only to corridor calls in a predetermined zone. In the presence of abnormal conditions, as detected by unit 139, all inhibits are removed, and the cars operate independently, the first car approaching a floor in the required service direction serving it. A dispatching scheme may also be rendered operative. Corridor call data for all floors may pass in parallel to the system processor, Fig. 2 (not shown), the latter passing parallel inhibit data to the selectors, or the corridor call data may be serialized for passage to the processor, providing serialized data to the car selectors, in which case each floor, has a binary address, and a corresponding time slot in a scan controlled by counter 164, an inhibit logic for each car removing the inhibit for the corresponding selector when, (i) the scan slot corresponds to a floor allocated to the car, or (ii) inhibits are removed in dependence on the relative magnitude of the address of the reference floor, and the position of the current slot in the reference scan, Fig. 5 (not shown). Within a given system, a binary mod signal (MODO, MOD1) Fig. 6 (not shown), together with a direction signal (UPSV) defines which of mode i) or any one of modes ii) is operative. When a programmable processor is used, the program is used to adapt the system to a particular building and defines the character(s) of the inhibit mode(s) used. The system can be expanded, to increase the number of controlled cars, on a modular basis. The program can include a diagnostic routine for malfunction diagnosis. Car calls. Car calls are multi-plexed for transmission to a car controller (216), Fig. 7 (not shown), passing in time division multi-plex at high voltage, and a lower rate than the corridor call serialization sequencing, car call resets, on initiation of car deceleration, are multiplexed to the car, there being memory elements for the car calls within the car, and possibly built into the car buttons, the memories being interrogated by the multi-plexer. There may be two spaced sets of call buttons within each car, Fig. 8 (not shown), multi-plexed to each other and to the controller, the sets thus appearing to the user to be in parallel, use of either one setting a corresponding indicator in both lines. Only for call set; for use in testing the system, setting car calls from the engine room; call reset, clock, and synch., need be provided in the travelling cable, and auxiliary car data, such as its state of loading may be included in the data multi-plexed to the car controller. A complete system is disclosed with reference to Figs. 11-35 (not shown) and includes, for noise immunity, optical data transmission, using optically coupled photoemitter, photodiode pairs. Dummy car calls may be used to park cars at predetermined floors determined by the programme, neither the car doors opening, nor the hall lamps being illuminated, when a car arrives at a floor in response to such a call.